/*
 * Copyright 2021 DataCanvas
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.dingodb.calcite.rule.dingo;

import io.dingodb.calcite.DingoRelOptTable;
import io.dingodb.calcite.rel.DingoRepeatUnion;
import io.dingodb.calcite.traits.DingoConvention;
import io.dingodb.calcite.traits.DingoRelStreaming;
import org.apache.calcite.plan.Convention;
import org.apache.calcite.plan.RelOptTable;
import org.apache.calcite.plan.RelTraitSet;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.convert.ConverterRule;
import org.apache.calcite.rel.logical.LogicalRepeatUnion;
import org.checkerframework.checker.nullness.qual.Nullable;

public class DingoRepeatUnionRule extends ConverterRule {
    public static final Config DEFAULT = Config.INSTANCE
        .withConversion(
            LogicalRepeatUnion.class,
            Convention.NONE,
            DingoConvention.INSTANCE,
            "DingoRepeatUnionRule"
        )
        .withRuleFactory(DingoRepeatUnionRule::new);

    public DingoRepeatUnionRule(Config config) {
        super(config);
    }

    @Override
    public @Nullable RelNode convert(RelNode rel) {
        final LogicalRepeatUnion union = (LogicalRepeatUnion) rel;
        RelOptTable relOptTable = union.getTransientTable();
        if (relOptTable == null) {
            relOptTable = DingoRelOptTable.getDefault(rel.getCluster());
        }

        final RelTraitSet traitSet =
            union.getTraitSet().replace(DingoConvention.INSTANCE).replace(DingoRelStreaming.of(relOptTable));
        RelNode seedRel = union.getSeedRel();
        RelNode iterativeRel = union.getIterativeRel();
        return new DingoRepeatUnion(
            rel.getCluster(), traitSet,
            convert(seedRel, seedRel.getTraitSet().replace(DingoConvention.INSTANCE)),
            convert(iterativeRel, iterativeRel.getTraitSet().replace(DingoConvention.INSTANCE)),
            union.all, union.iterationLimit,
            union.getTransientTable());
    }
}
